Dc brushless motor control system applicable for ac power

Abstract

A control system electrically coupled between a main control module and a DC brushless motor includes a switching power conversion circuit, a voltage conversion circuit, a central processing circuit, a motor driving circuit and a switching circuit. The switching power conversion circuit is connected to the air-conditioning main control module for receiving an AC power, and rectifying, bucking and filtering the AC power to form and supply a stable DC power for the operation of the DC brushless motor, so that a conventional air-conditioning system converts AC signals into DC signal to control and drive DC brushless motor, so as to achieve the power saving effect without the need of changing the existing pipeline wiring and control interface.

What is claimed is: 
     
         1 . A DC brushless motor control system applicable for AC power, comprising:
 at least one switching power conversion circuit, for receiving an AC power, converting the AC power into a DC power;   a voltage conversion circuit, coupled to the switching power conversion circuit, for converting the DC power into at least one driving voltage;   a central processing circuit, coupled to the switching power conversion circuit and the voltage conversion circuit, for receiving the driving voltage;   a motor driving circuit, coupled to the voltage conversion circuit and the central processing circuit, for receiving the driving voltage and a signal of the central processing circuit, and converting the signal into a driving signal; and   a switching circuit, coupled to the motor driving circuit and the voltage conversion circuit, for receiving the driving signal.   
     
     
         2 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the switching power conversion circuit includes a rectification element, a current limiting element, a voltage regulation element and a filtering element coupled to one another. 
     
     
         3 . The DC brushless motor control system applicable for AC power according to  claim 2 , wherein the rectification element includes a plurality of serially connected diodes. 
     
     
         4 . The DC brushless motor control system applicable for AC power according to  claim 2 , wherein the current limiting element is coupled between the rectification element and the voltage regulation element, and the current limiting element includes at least one resistor. 
     
     
         5 . The DC brushless motor control system applicable for AC power according to  claim 2 , wherein the voltage regulation element is coupled between the current limiting element and the filtering element, and the voltage regulation element includes a diode and a Zener diode connected in series with each other. 
     
     
         6 . The DC brushless motor control system applicable for AC power according to  claim 2 , wherein the filtering element includes at least one resistor and a capacitor coupled to each other. 
     
     
         7 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the control system further includes a Hall component coupled to the voltage conversion circuit and the central processing circuit. 
     
     
         8 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the switching circuit is a transistor. 
     
     
         9 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the central processing circuit selects a sine wave driving mode or a square wave driving mode. 
     
     
         10 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the central processing circuit detects different inputs of AC power at a front end as a basis for determining a rotational speed of the DC brushless motor. 
     
     
         11 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the central processing circuit modulates a voltage inputted to the motor by a pulse width modulation method. 
     
     
         12 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the control system is applied in an air-conditioning system, and the air-conditioning system comprises a main control module and a DC brushless motor, and the control system is electrically coupled between the main control module and the DC brushless motor, and the switching circuit is coupled to the DC brushless motor for driving the DC brushless motor to operate. 
     
     
         13 . The DC brushless motor control system applicable for AC power according to  claim 12 , wherein the air-conditioning system has an outdoor end and an indoor end, and both ends of the DC brushless motor are coupled to a fan separately, and the two fans are configured to be corresponsive to the outdoor end and the indoor end respectively. 
     
     
         14 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the control system is applied in an air filter system, and the air-conditioning system includes a main control module and a DC brushless motor, and the control system is electrically coupled between the main control module and the DC brushless motor, and the switching circuit is coupled to the DC brushless motor for driving the DC brushless motor to rotate. 
     
     
         15 . The DC brushless motor control system applicable for AC power according to  claim 14 , wherein the air filter system has a suction end and a discharge end, and the DC brushless motor is coupled to a fan, and the fan is installed between the suction end and the discharge end. 
     
     
         16 . The DC brushless motor control system applicable for AC power according to  claim 1 , wherein the control system is applied in a dehumidification system, and the air-conditioning system includes a main control module and a DC brushless motor, and the control system is electrically coupled between the main control module and the DC brushless motor, and the switching circuit is coupled to the DC brushless motor for driving the DC brushless motor to operate. 
     
     
         17 . The DC brushless motor control system applicable for AC power according to  claim 16 , wherein the dehumidification system has a suction end and a discharge end, and the DC brushless motor is coupled to a fan, and the fan is installed between the suction end and the discharge end.